Bladed disk for radial flow rotary machines



Miartthy 14, 1944. Y U ME|N|NIGYHAU$ 2,344,099

BLADED DISK OR RADIAL FLOW ROTARY MACHINES Filed Nov, 16, 1940 5 'Sheng-sheet 1 y I 17, W fr ATTORNEYS March 14, 1944. U ME|N|NGHAUS' 2,344,099

BLADED 'msx Fon RADIAL FLow ARonny MAcHINEUsv Filed Nov. 1s, 1949 sfsheets-shee' 2 /l f l m ,I 7 f ATTORNEYS l [Il AI l Mrch 14, 1944 U. MEININGHAus 2,344,099

l I BLADED DISK FOR RADIAL FLOW ROTARY MACHINES Filed Nov. 1e., 1940 ls sheets-sheet s C "Il L g /lll Y;

mu uu um @zu gENToR i ATTORNEYS March 14, 1944. U, MEIMNGHAUS 2,344,099

BLADED DISK FOR RADIAL FLOW ROTARY MACHINES Filed/Nov. 1s, 1940 5 sheets-sheet 4 March 14 1944- U. MEININGHAUS 2,344,099 I BLADED `DISK FORQRADIAL FLOW ROTARY MACHINES Filed Nov. 1e, 1940 ssheets-sheet 5 VII I Il

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Emp@ l -`Bvg E v ATTORNEYS.

Patented Mar. 14, 1944 VBEADED DISK FORRADIAL FLOW ROTARY MACHINES `.Ulrich ,Meininghausf .Mulheim-Ruhn Germany; `vested in the Alien`lroperty 'Custodian AV--A-pplicationNovember 16, 1940,- Serial No. 365,892

fInlGermany November.21,'.1939

. iiClaims.

The present invention v:relates y.to the '.bladed wheel V construction A.of `rotary fma'chines, and especially .of radial 'lflow steamand:gas turbines.

- It Vislthe general obj ect A'tlthe :invention to-pro vide an improved .diskfor.radial'iiowengines which is capable of withstanding 'axial thrusts even if at the same time a great temperaturevdrop exists between bothsides -oftheinner part of the WheeLand. in particular alWheel-which keeps its strength when the connection-of wheel-and shaft is elastic in order to allow fforffreeexpansion and Accntractionof the wheel due vto temperature changes. Other, .more'spe'cific .objects of the invention will rappear iromthe detailed description hereinafter.

The 1.accompanying drawings .illustrate by way `of exampledifferent embodimentslof the .invention. f Figs. 1..tol3 ofl theaccompanyingdrawings are vertical fragmentary sections through three different forms of. bladed disks for l.avradial :flow steam! turbine constructed: accordingto the .invention; Fig.'4 is a .sectionuthrough the whole turbine; Fig. 5 is an enlargediragmentary4 vertical section .through .the central v.portion '.of a modified form4 otbladed Idisk.

.In Fig. l,.the Wheelc I -isshrunk.on/the shaftl 2 at3 andlbylmeansof the elasticring Ir. rIlhe end of the ring. IrshrunkiatiS `is :pressed against the shouldercf theshaft Zibythe .thrustcfithe wheel I. The .nut l, isannadditional safeguard toholcl the wheelinplace. The rings 3r-'I 9T.. are

tween .the rings. "Especiallyithe .inner ring x31-, but: also "the adjacent. ringsxr, "1r, etc., VV.would takeY an oblique .position 1in. cases` of; wheels with.

undivided rings and s websY as the-:steamentering at theleft from the .centerisrconsiderably hotter thanthe steam leaving'zinwar'dly .at the right.l

The right end of "therings;would' be :colder :than

the `hot left-end, and therefore the diameter of.4

side of the disk. To diminish this Obliquity, I cut l a notch with a saw along the median plane of the wheel. This notch, being lled with an insulating layer of the driving medium increases the resistance to the flow of heat in such a way that the degree of Obliquity of the rings is limited to non-dangerous values. That the notch 20 of Figure 1 does not prevent the iiow of heat along the ri-ngl Ir is no `disadvantag'easthis ring. represents an .1 elastic joint between wheeltand vshaft the ltask of `which is `not tostrengthen the. disk. It is only' of advantage that the-stresses-off-this elastic jointare relievedby the now-of heat.along it. andk by the corresponding Obliquity.

vliig.2, to 'Whichthesame referencenumerals apply, illustrates.. a construction with two..` entirely separated and then assembled; halves of the wheel. The half. 2l is connected ywith thehalf I by means of the elastic 4jointi-22 and-the calking Wire .23. The .torque of the halfrZI is transferred tothe half. I through v.inter-,engaging .notchesand projections 24. The fhub consistingof the rings Ir and13r and Web2s carries Aboth halves.

Fig.'3 showsa construction especially adapted forhgh steam pressures. Thesteamentersthe bla'dingl32 yat the inner .diameteriand ows- .from the outer circumference of. thisblading to .the blading'33 which.is.-.traversed inwardly. To restrict the flowvof heat and .to securea freedomof expansion thewheel has beendivided into parts 34 `and 35. Diiiiculties arise Ain joining the two halves in asuiciently elastic Wayandz keeping the joint at: the samev time absolutely: tight :at highsteam pressure. andptemperature. 1I .provide for this .purpose an elastic .member 36 of circular crossfsection. This elastic member IV fasten .to the hub of the wheel .3| by calking .in the end'l thereof in a suitable notch with a softwire 38, and fasten it also Vto theinnerpart of the half A34 byinsertingithe endfSQ of. themember in anot'ch the wall 4I) of which is expanded to enlargexits diameter by a special tool. The main task of the elastic member 36 consistsin bridging the variations in diameter occurring between the vtwo halves of the-Wheeldue to vdifferences in the mean temperature or centrifugal forces. As the end 31 ofthe member extendsina radial direction, any variation in diameter ofl this /end causes rolling action -inside the area ofthe circumference. `Thisrolling :action -is similar to the windingl of thespring of a ,watch and gives .rise to a comparatively equal distribution of the deformations across the total cross section of the circumference and avoids any dangerous local rise of the stresses at the points where the ends are clamped.

The rolling action will always be obtained when at least one end of the circular cross section to which the circumference of the annular elastic member is shaped to withstand the pressure runs at an angle of less than 45 to the direction in which the moving of said end is efand carries the wheels 42, 43 and 44 with the blades 45, 46, 41 and 48. The wheel 43 corresponds with Fig. 3. The disks 49 and 50 hold the stationary blades 5|, 52, 53 vand 54. The steam enters through the nozzles 55, passes the impulse blade row 56 and then the reaction blading 5|, 52, 53 and 54. The axial thrust ofthe reaction blading is balanced by the labyrinth disc 51. 58 represents the housing of the turbine.

Obviously, my invention is not restrictedto rotary machines of the specic form illustrated, but for example may be used with wheels along which the working medium flows in the same direction on both sides, but with different temperature. Or the one side of the wheel may carry blades, the other side labyrinth packing.

The turbine wheel shown in Fig. 5 represents a simplified construction for high pressure. The wheel 6| carries'the blades 62 and 63 with the carrier rings 64 and 65 which are out from the material of the disk halves 66 and 6l. At the inner circumference of the half 66 a special ring 68 is cut from the material of the disk, such ring extending in the same direction as the rings 64. An additional ring 69 runs parallel to the ring 68 in the same direction and is cut from the material of the half 61. Both rings 68 and 69 are united at their ends by shrinking 68 on 69. The ring 68 is made thinner and more elastic than the rings 64, the ring 69 thicker and stiffer than the rings 65. The ring 69 may thus reinforce the whole assembly. The joint between the rings 68 and.69 at their ends is the only contacting area in axial direction between the two disk halves along the at least half the radius thus allowing for free expansion of the rings 58 and 69. The whole assembly is supported by means of the flexible ring 10.

I claim:

l. A blade carrying disk for radial flow rotary machines, in particular steam or gas turbines, having axially extending rings formed by grooves cut into the body ofthe disk down to a certain residual depth and carrying blades at the outer ends, the disk being supported at the inner diameter, and being provided with an insulating space extending radially through the disk in the region covered by said axially extending rings, said space being open at the periphery of the disk throughout substantially the whole extent thereof and acting vto diminish the temperature drop between the bladed ends and the roots of Y 'f 3. A disk according to claim 1, wherein paral- `lel to a ring cut from the circumference from one disc half and extending in the same direction as the carrier rings of such disk half, an additional ring runs in the same direction from the other disk half, the ends of such two rings being Vunited with one another. ,4. A disk according to claim 1 wherein the disk is supported by an elastic member, thereby permitting the disk to expand and contract or totake an oblique position, the cross section of the elastic member being of circular shape with at least one end running at an angle of less than 45 to the radial direction, the elastic member being constructed and arranged to allow simultaneously for small movements in the axial direction.

5. A blade carrying disk for radial flow rotary machines, in particular steam or gas turbines, having axially extending rings formed by grooves cut into the body of the disk down to a certain residual depth and carrying blades at the outer ends, the disk being supported at the inner diameter, the disk having a slot extending radially through the disk in the region covered by said axially extending rings and cut from the outer circumference of the disk down to the hub along approximately the central plane of the disk, the space formed by such slot acting to diminish the temperature drop between the bladed ends and the roots of the rings by throttling the flow of heat from the one side of the disk to the other side.

6. In a radial flow turbine, the combination with the housing and inlet and outlet passages for a hot driving medium, of a blade carrying disk so arranged in the housing that it is exposed to diierent temperature conditions upon opposite sides thereof, said blade having axially extending rings formed by grooves cut into the body of the disk down to a certain residual depth and carrying blades at their outer ends, the disk being supported at its inner diameter, and being provided with an insulating space extending approximately radially through the disk along at least part of the region subtended by the axially extending rings, said space being open at the periphery of the disk throughout substantially the whole yextent thereof, and acting to diminish the temperature drop between the bladed ends and the roots of the rings by throttling the flow of heat from the one side of the disk to the other side.

' ULRICH MEININGHAUS. 

